Concrete pump



C. F. BALL Sept. 27, 1938.

CONCRETE PUMP Original Filed Aug. 19, 1951 4 Sheets-Sheet l ChaaEBaZl,

Sept. 27, 1938. I c. BALL 2,131,681

CONCRETE PUMP Original Filed Aug. 19, 1931 4 SheetsSheet 2 llql W lllllllll l L-wflll Sept. 27, 1938. c. F. BALL CONCRETE PUMP Original Filed Aug. 19, 1951 4 SheetsSheet 3 Sept. 27,1938. c F, BALL 2,131,681

CONCRETE PUMP Original Filed Aug'. 19, 1931 4 Sheets-Sheet 4 Patented Sept. 27, 1938 I UNITED STATES PATENT oFFIcE CONCRETE PUMP Charles F. Ball, Milwaukee, Wis, assignor to Chain Belt Company, Milwaukee, Wis., a corporation of Wisconsin 2 Claims. (01. 83-73) This invention relates to pumps of the reciprocating piston type and has for one of its objects to provide a pump of this character which will be particularly adapted for the pumping of concrete and other similar plastic mixtures which embody relatively large heavy aggregates.

A still further object of the invention is to provide a concrete pump having a receptacle for receiving pre-mixed, or partially mixed concrete, or even unmixed concrete making materials, which receptacle is adapted to mix and to maintain such concrete in completely mixed and unsegregated condition and to feed the same to the pump cylinders.

A still further object of the invention is to provide a concrete pump which will be more efiicient in action than those which have been heretofore proposed. 2 With the above and other objects in view which 20*will appear as the description proceeds, the invention consists in the novel details of construction and combinations of parts more fully hereinafter set forth and particularly pointed out in Y the appended claims.

25* Referring to the accompanying drawings forming a part of this specification in which like reference characters designate like parts in all the views:

Figure 1 is a side elevational view, partly broken away, of a concrete pump constructed in accordance with the present invention;

Figure 2 is a partial plan View of the parts shown in Figure 1, the concrete receiving and agitating drum, the power plant, and the fluid 35'pressure pump, being omitted and certain of the parts being shown in section;

Figure 3 is an end elevational view partly broken away, of the parts shown in Figure 1 as seen from the right of the latter figure;

Figure 4 is an end elevational View, partly broken away, of the parts shown in Figure 1 as seen from the left of the said figure, the power plant and certain other parts being omitted for- I the sake of clearness;

45 Figure 5 is a fragmentary side elevational View of the rear end portion of the apparatus, as seen from the side opposite to that shown in Figure '1, and showing the fluid pressure pump;

Figure 6 is a fragmentary vertical sectional 'view through the outlet conduit showing a slightly modified form of outlet valve construction;

Figure 7 is a diagrammatic view illustrating the fluid circuits between the fluid pressure pump, the control valve and the concrete pump pistons;

55 and Figure 8 is a fragmentary sectional elevational view, showing the means for automatically shift ing the fluid control valve.

In the said drawings the numeral It indicates a main frame of substantially rectangular con- 5' struction, which may be stationary if desired, but which is here shown as being mounted upon suitable wheels II, in order that the pump may be portable and moved from place to place as desired. The said frame It is here shown as com- 10 prising the longitudinal side channels l2 and I3, and the transverse members I4, l5, I6, I 1 and is, rigidly connected in any suitable manner to the said channels. As best shown in Figures 2, 3

and 4, the transverse member l5 carries a pair of 15' clamping blocks 20, While the member I! carries a companion pair of blocks 2!, which pairs of blocks receive and hold the longitudinally extending shafts 22, ,upon. which are rotatably mounted the drum-supporting rollers 23. A concrete receiving and agitating drum 24 is mounted for rotation in either direction upon the rollers 23, which drum is or may be of substantially the construction commonly employed in rotatingdrum concrete mixer practice. The said drum is 25 provided with the axial charging and discharging openings 25 and 26,- respectively, into the former of which extends a charging hopper 2'! carried by suitable upright supports 28. The interior of the drum carries the well known helical mixing blades 29, arranged to thoroughly mix the constituents when the drum is rotated in one direction, and which also serve to move the concrete from right to left, as viewed in Figure 1,

toward the discharge opening 26 when the drum is rotated in the opposite direction; and the discharge end of the drum is preferably provided with the transverse curved pick-up and discharge troughs 3B, which through the rotation of the drum in the last mentioned direction, pick-up and 40 positively move the concrete to and through the discharge opening 26, all as is disclosed and claimed in my copending application filed June 24, 1931, Serial No. 546,591, now Patent No. 2,006,728, granted July'2, 1935;

The discharge opening 26 of the drum communicates with the horizontal passage 31 of a chest 32, which, as is best shown in Figure i, is provided with a pair of downwardly extending discharge passages 33, each leading to a valve housing 34. The chest being stationary, whereas the drum is rotatable, a suitable slip joint or running seal 35 is provided between the two, to prevent escape of the concrete. The valve housings 34 are each provided with chambers 49.

a seat 36 for receiving the ball valves 31, which constitute the intake valves of the cylinders of the concrete pump. The balls 31 are preferably hollow, to increase their tendency to rise toward their seats, and they may, if desired, be covered with rubber or similar yielding material to render their seating more certain. Suitable fingers or retainers 38 are provided in the housings 34 to limit the outward movement of the balls.

Each inlet valve housing 34 is secured to and communicates with the open end of a horizontal pump cylinder 49. As will be clear from Figure 2, these cylinders are disposed longitudinally of the frame 18 in spaced parallel relation, and are secured to and supported by the transverse frame members l5 and It. In each cylinder there is mounted for reciprocation a hollow piston 4|, having a solid head 42 provided with a cupped packing 42, sealing the piston against the passage of liquid there around. Each piston 4| is also provided with an elongated tubular skirt 43, see Figure 1, which skirts are of somewhat smaller diameter than the heads 42 and cylinders 48, and are closed at their ends opposite to the heads by removable cross-heads 44, apertured asat 45 to accommodate the horizontal'rods 45, rigidly supported by the end transverse member 18, and arranged coaxial with, and extending into, the said skirts. The said rods 46 carry at their free ends abutments 41 having packing rings 48 slidably engaging the interior surface of the skirts and providing within the latter two chambers 49 and 50.

Each rod 46 is provided with a longitudinally extending duct or passage 5! through which fluid may be! alternately introduced into and exhausted from the chambers 49, as will appear more fully below; and each rod is further provided with a second duct or passage 52, communicating with the chambers 59. The latter passages are connected exteriorly of the pistons by a pipe 53, see Figures 2 and '7, whereby fluid may flow freely back and forth between the two chambers 5!].

For supplying fluid under pressure to the cham-- bars 49, whereby the pistons 41 may be reciprocated, there is provided any suitable fluid pres sure pump 55, driven by an internal combustion engine or other source of power enclosed within .a housing 53 mounted on the frame ill. The said pump 55 forces fluid, e. g. oil, through a pipe 51 to a control or distributing valve 58, from which it is fed alternately to pipes 59 and 60, each of which leads to one of the passages 5| in the rods 48, which communicate with the When the valve is in such position that it is feeding fluid to the pipe 59, for example, the said valve has placed the companion pipe 58 in communication with a return pipe 6| leading from the valve back to the pump 55. As the fluid is forced through the pipe 59 and passage 5| into a chamber 49, it reacts against the abutment 41 and moves the piston 4| toward the left, as viewed in Figure 1, the skirt 43 sliding over the abutment, and the crosshead 44 sliding on the rod 46; This movement reduces the size of the chamber 58 and forces the oil therein out through the passage 52 and pipe 53 to the other chamber 59, where it reacts upon the other cross-head 44 to move that element and its associated skirt 43 and piston head 42 toward the right. The fluid pressure in one chamber 49 thus moves one piston 4| in one direction, and simultaneously through the medium of the fluid in chambers 58, passages 52 and pipe 53, moves the other piston in the opposite direction; and when the valve 58 changes the feed of fluid to pipe 68, the motions of the respective pistons will be reversed. On each movement toward the right, as seen in Figure 1, each piston 41 will draw concrete into its cylinder 48 from the chest 32 through its respective inlet valve 31, and on the return stroke will force it out of the cylinder again, as will be readily understood.

A by-pass pipe 62 is provided between the fluid pump 55 and valve 58, through which the oil may be returned to the pump, upon manipulationof the hand lever 63, without passing to the chambers 49, when it is desired to stop the concrete pump without stopping the fluid pump.

The chambers 58 are filled with oil at the outset, and except for leakage, there is no flow of this oil other than back and forthbetween the said chambers. Some oil from the chambers 49 however, will pass the packing rings 48 on the abutments 4l,'into the chambers 58; and should pressure in these latter chambers become excessive, the pressure will open a relief valve 64, permitting the excess oil to return through .a pipe 65 to the pump 55., A branch 66 of this pipe leads back to the valve 58.

The details of the fluid pump 55 and of the valve 58 form no part of the present invention, those illustrated being in common use and procurable in the open market.

One means of automatically actuating the valve 58 to reverse the fluid flow is shown in Figure 8. A pair of arms 19 and ll are pivotally hung as at 12 and it, on the side frame member i2, and their lower ends are connected by a rod- 14 on which is mounted a pair of spaced adjustable stops !5 and 15, which are engageable by one of the cross-heads 44 as it ,approaches'each end of its stroke. The rod [4 is thus moved, first in one direction and then in the other, and such movements are, transmitted through the arm II and linkage 17 to the valve 58, whereby it is caused to direct the oil from pipe 51 alternately to pipes 59 and 68. 1 7

Each valve housing 34 is provided with an outlet opening 88, communicating with an outlet conduit 8|, leading to an outlet valve housing 82. This housing is provided with a pair of opposed seats 83, and a single outlet valve ball 84, of similar construction to the balls 3'1, is mounted therein between guides .85. The ball 84 shuttles back and forth horizontally between the seats 83, in response to the alternate pressures exerted on the concrete bythe pistons 41, and a single valve ball thus controls the discharge from both cylinders 48. Thehousing 82 has a discharge passage 86, provided with a connection 8! to which the distributing pipe or conduit may be attached. The usual equalizing air pressure chamber 88 may be mounted on the said connection 81.

In the slightly modified construction shown in Figure 6, separate outlet valves 84' are employed for each cylinder, and in this instance. the balls move at an angle of approximately 45 instead of horizontally, as when only one valve is used.

The motor within the housing 59, in addition to driving the fluid pump 55, also furnishes power for rotating the drum 24. Power from the motor shaft may be taken by a chain 98 to a worm reduction gearing within a casing 9|, and thence by a sprocket 92, chain 93 and sprocket gear 94 to the said drum. 3

The cross-heads 44 are preferably mounted and slide upon fixed guide rods 95, extending be-- tween and rigidly fixed to the transverse frame member 18 and the enlarged ends 40' of the cylinders 40, see Figure 2.

Eachcylinder 40 is provided at its right hand end, as viewed in Figures 1 and 2, with a washwater chamber 96. The said chambers are interconnected by a pipe 91, see Figure 2, into which leads a water supply pipe 98, and each chamber is further provided with a bleeder outlet 99. The wash-water within the said chambers for the most part merely moves back and forth in the cylinders 46 behind the piston heads 42, in the same manner as does the oil in the chambers 50. A slight flow of wash-water is provided however, from the supply pipe 98, due to the slow dis charge through the bleeders 99.

The volume of the fluid supplied to the pump is practically constant, and therefore the movement of the pistons 6| in the cylinders 40, back and forth, is uniform throughout the entire length of their stroke. Since one piston picks up immediately where the other leaves 01f, and at the same speed, the concrete in the delivery pipe is kept in continuous motion and a smooth flow of concrete, substantially without pulsations, emerges from the distributing pipe. It is important to keep the concrete in continuous motion, since any stoppage, even for short periods, requires relatively great increase in pressure to overcome the static friction between the concrete and the walls of the distributing pipe and to restore kinetic energy to the concrete. Any stoppage of the movement of the concrete, even for comparatively short periods, introduces the liability of segregation, and also adherence, hardening and building up of the concrete on the various surfaces of the apparatus.

Clean-out holes are provided at suitable points in the various passages, which are normally closed by cover plates I00.

This application is a division of my prior copending application filed August'19, 1931, Ser. No. 558,175, entitled Concrete pump now Patent No. 1,991,342, granted February 12, 1935.

It is obvious that thoseskilled in the art may vary the details of construction as wellas. the 7 a chest having a horizontal portion communicating with said opening to receive material therefrom, said chest also having a plurality of depending legs each communicating with a cylinder; a running seal between said drum and the horizontal portion of said chest; means in said drum arranged to agitate and move the material through said opening into saidchest; and valve means arranged to prevent materialin the cylinders from flowing back into the legs of said chest.

2. In mechanical pumping apparatus for plastic concrete mixtures embodying substantial proportions of coarse aggregate, a pressure concrete pump having a plurality of working cylinders each provided with an inlet; a rotatable concrete receiving and agitating drum mounted above said pump and having an end discharge opening; a chest having depending legs surmounting the inlets of the respective pump cylinders, and a lateral extension communicating'with said d-rum opening, and providing closed passages between said opening and inlets; and means in said drum for discharging concrete from said drum into said chest extension faster than the pump withdraws it from the chest, whereby to keep said closed passages constantly filled with the mixture and segregation of the latter prevented.

CHARLES F. BALL. 

